Designing a toilet for an aircraft poses challenges that do not generally occur in ground-based toilet designs. For instance, in an aircraft, space and weight are at a premium, and using regular water-flush toilets is not practical. Also, performing routine maintenance and cleaning is much more difficult, since space restrictions make access to plumbing nearly impossible.
Flushing devices for an aircraft vacuum toilet generally require that after the use of the toilet, a flushing processing is actuated by triggering device. This is then followed by the supply of flushing liquid to the toilet bowl and subsequent opening of a suction valve, so as to pull waste, flushing liquid, and any other impurities into a waste tank.
Vacuum toilet systems often include a maintenance switch that permits operation for ground maintenance. However, there are drawbacks associated with existing systems. For instance, maintenance switches are often difficult to access.